Shareware and demo versions of software have outgrown the third- rate image with which they were once saddled, and with developers such as id Software using them as a marketing channel, they've become an important means of distribution for publishers.

Shattered Steel, a 3D blast 'em, is one of the latest doing the rounds as a cut-down playable preview on magazine CD-Roms and on the Internet. Even though it has limited levels compared with the retail version, it's still a hefty chunk of software. There is a minimum playable version at 7.5mb or the full preview at 12mb. When Interplay's server is busy - and it often is - that spells fat profits for the phone company.

The action is located in deep space in the 22nd century, where frontier worlds are ruled by corporations with their own genocidal forms of law and order enforcement. Out of that arises the far-from-original game scenario that you're a mercenary in a hi-tech vehicle with a brief to roam alien planets nuking everything that moves. No high-falutin pretensions here. The vehicle is a Planet Runner, a radar-equipped all-terrain device which looks like a cross between a tank and a drunken Velociraptor and, of course, carries more firepower than mere 20th century despots could ever aspire to.

Although described as all-terrain, Planet Runners are not the most straightforward of craft to control, especially when subject to laser bombardment from the vehicles of the miscreants you're trying to reduce to component pixels. However, once you get the knack of controlling movement and aiming, the game comes to life.

Graphically, it's polished and the animation is quick and responsive. The limited preview can be worked through in a couple of days, but the full version has much more - 50 missions, 16-player network battles, team missions and head-to-head modem and serial capabilities.

One of the chief attractions, other than that it's a stylish example of its genre, is that the full version will work with BioWare's mission editor, which allows players to design and play their own missions. This is another shrewd piece of marketing; those games which support such a feature build up incredible player loyalty, and sales, as people persuade their friends to buy the game so that they can try out some home-made missions.

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